Re: [PATCH v2 01/36] soc: fsl: cpm1: qmc: Update TRNSYNC only in transparent mode

Christophe Leroy
2024-08-23T08:03:38Z

Le 08/08/2024 à 09:10, Herve Codina a écrit :
> The TRNSYNC feature is available (and enabled) only in transparent mode.
>
> Since commit 7cc9bda9c163 ("soc: fsl: cpm1: qmc: Handle timeslot entries
> at channel start() and stop()") TRNSYNC register is updated in
> transparent and hdlc mode. In hdlc mode, the address of the TRNSYNC
> register is used by the QMC for other internal purpose. Even if no weird
> results were observed in hdlc mode, touching this register in this mode
> is wrong.
>
> Update TRNSYNC only in transparent mode.
>
> Fixes: 7cc9bda9c163 ("soc: fsl: cpm1: qmc: Handle timeslot entries at channel start() and stop()")
> Cc: stable@vger.kernel.org
> Signed-off-by: Herve Codina <herve.codina@bootlin.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
> drivers/soc/fsl/qe/qmc.c | 24 ++++++++++++++----------
> 1 file changed, 14 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/soc/fsl/qe/qmc.c b/drivers/soc/fsl/qe/qmc.c
> index 76bb496305a0..bacabf731dcb 100644
> --- a/drivers/soc/fsl/qe/qmc.c
> +++ b/drivers/soc/fsl/qe/qmc.c
> @@ -940,11 +940,13 @@ static int qmc_chan_start_rx(struct qmc_chan *chan)
> goto end;
> }
>
> - ret = qmc_setup_chan_trnsync(chan->qmc, chan);
> - if (ret) {
> - dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
> - chan->id, ret);
> - goto end;
> + if (chan->mode == QMC_TRANSPARENT) {
> + ret = qmc_setup_chan_trnsync(chan->qmc, chan);
> + if (ret) {
> + dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
> + chan->id, ret);
> + goto end;
> + }
> }
>
> /* Restart the receiver */
> @@ -982,11 +984,13 @@ static int qmc_chan_start_tx(struct qmc_chan *chan)
> goto end;
> }
>
> - ret = qmc_setup_chan_trnsync(chan->qmc, chan);
> - if (ret) {
> - dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
> - chan->id, ret);
> - goto end;
> + if (chan->mode == QMC_TRANSPARENT) {
> + ret = qmc_setup_chan_trnsync(chan->qmc, chan);
> + if (ret) {
> + dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
> + chan->id, ret);
> + goto end;
> + }
> }
>
> /*